Valve for gas-engines.



PATENTED JULY 16, 1907.

P. SGHWEHM. VALVE FOR GAS ENGINES, APPLICATION FILED FEB. 2s. 1907.

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UNITED STATES PATENT OFFICE;

PETER SCHWEHM, OF HANOVER, GERMANY.

Specification of Letters Patent.

VALVE FOR. GAS-ENGINES.

Patented July 16, 1907.

No. 303,581. Divided and this application iiled February 23, 1907.

Serial No. 368.785.

To all whom it may concern:

Be it known that 1, PETER SCHWEHM, a citizen of Germany, residing at Hanover, Germany, have invented new and useful Improvements in Valves for Gas-Engines, of which the following is a specification.

This invention relates toa valve for gas engines which provides means for effectively controlling the inflow oi air and gas independent from the main inlet valve. Further, means are provided for separately admitting charge air and scavenging air into the cylinder, so that low pressure may be used for expelling the dead gases, while the exit ports are open, and that furthermore, the cylinder may be charged under high pressure, after the exit ports have been closed.'

This application is a division of an application iiled by me March 1, 1906, under Serial No. 303,581.

In the accompanying drawing: Figure 1 is a longitudinal section through my improved valve; Fig. 2 a similar section through a modification thereof,- `and Fig. 3 a diagrammatic viewoi the cam for operating the valve.

Through a housing 5 extends axially a solid stem 6 which is embraced by a sleeve 7. To the lower end of stem 6 is secured'inlet valve 8 and a slide valve 9, which controls thevadmission of air from an air pipe l0. Sleeve 7 carries at its lower end slide valve 11, which controls 'the admission of gas from gas pipe 12. Slide valve 9 is provided withopenings 13, 14, of which the openings 13 admit the air of the explosive charge, while openings 14 control the inow of the scavenging air both charge air and scavenging air being admitted through pipe 10. Openings 15 in slide valve 11 control the inflow of gas. 1t will thus be seen that the commencement and end oi the period ior admitting charge air and scavenging air into the cylinder does not depend upon the operation of inlet valve 8, but is also controlled by slide valve 9. In this way, by selecting the size, number and relative position oi'openings 13 and 14 for each individual machine, the pressure of the charge air and scavenging air may be readily controlled. The smaller the combined area of openings 14, the less scavenging air will be admitted into the cylinder, and as the air admitted always occupies the same space, its pressure will be correspondingly reduced.

The stem 6 of Valves 8 and 9, is influenced at its upper end by a spring 16 engaging a disk 24 fast on said stern and slidable in a housing 22. At its lower end stem 6 carries areliei plunger 17 engaging a cylinder 18 arranged within mixing chamber 19. Cylinder sure pipes 10 o r 12 through a branch 23, in which case plunger 17 at the lower end of stem 6 is dispensed with.

By the construction described, two advantages are' obtained, vizz-firstly, the pressure of scavenging air and of the intlowing charge may be'reduced to any desired minimum (by reducing the area ot'openings n 13, 14 and 15), While the exit ports of the engine cylindelare opened, such pressure being independent from the tank pressure.4 Secondly', the period dur- `ing which the inlet valve 8 may be held open, without loss, may be prolonged, for the following reason: With two-cycle gas engines having inlet valve-gear, the inlet valve is usually opened when the piston is at the dead center and is closed when the shaft has been rotated for about As the valve must have a longstroke to obtain the necessary opening for the admission oi the charge, the cam for operating the inlet valve, heretofore received a form which caused much noise and heavy wear. By iurnishing a separate control for the inowing gas and air, the inlet valve 8`may be opened earlier and closed later than with the prior constructions. y

lf the openings 14 controlling the inflow of the scavenging air are so dimensioned that when valve 8 is opened, the pressure in mixing chamber 19 is equal to that within the tank that furnishes said air, the valve 8 may be opened at the moment when the pressure of the waste gases is equal to the pressure in chamber 19. In this way exploded gases will not be4 able to enter the mixing chamber.

If the openings controlling the inflow ofthe cleaning air are properly dimensioned` waste o air may be avoided. After the scavenging period, during which the engine shaft turns through twenty degrees Ahas ceased, the'charging period commences, air and gas entering simultaneously through openings 13, 15, respectively. When the shaft of the engine has been further rotated for about 70, slide valve l-1 is closed, While slide valve 9 remains open until the desired charge pressure is obtained, whereupon the air is also cut off. The inlet valve 8 :may thus remain open during a further movement through 20, after the engineshaft has been rotated tor 70, as above set forth, without any considerable waste. Thus by the construction desbed7 the angle Of rotation during which the inlet 1'01' ilnie elmlg'e nir nlnd scavenging aix'. n ,Qns valve opel'- Valve is held Upon mrw be extended :mm 70o t() ated independentlyfrom the an valve. :md a relief plun- 10 o ger seamed lo the inlet vnlve,substantially :is .speeiiied fLbOut 110 (llg- 3), S0 that ShOCkS are ldllCGd and Signed by me :1t Hanover, Germany. this eleventli day heavy wear is avoided. et February 11m?.

I claim: f y. PETER sCHwmIM. In a valvegfor gais engines, am inlet port. and an inlet Witnesses:

valve controlling said ppi-t. combined with an air valve 1.\VL R. 'l1m.\us

carried by the inlet valve and having two sets of openings .Hur-:s M. BUCOCIL 

